The present invention relates to a device and method for implementing a key in a keypad.
Many electronic devices include a user interface to implement functionality for user input and output. There are various ways of implementing the user interface, utilizing communication by voice, picture, text, the sense of touch or other signalling methods. The most common type of user interface continues to be based on key functions implemented by means of a key pad; the device outputs data to the display, and the user enters input in the form of alphanumeric characters, using the key pad.
A touch screen is a type of combination of key pad and display; the display is typically fitted with a sensor matrix to detect finger presses on the screen surface and indicate their position. The display control system has been programmed to recognize finger presses on a certain area of the screen as commands for the user interface; the user can input data by touching certain areas indicated on the screen. Thus, one of the benefits of a touch screen over a conventional combination of a key pad and display is that the former can be customized in software, by using so-called SOFT keys. On a touch screen, the user interface can at one moment be a game controller, on another moment it may represent a Chinese keyboard.
A disadvantage of the touch screen compared with a conventional combination of a key pad and display is that the touch screen is unable to give the user a feeling of the key presses. By grounds of its accuracy, key operation based on the sense of touch feels familiar and reliable for the users. Users want the keys to be distinguishable from the underlying surface and to move down with the key presses. Touch screens also cause problems for the weak-eyed, who are unable to distinguish adjacent option keys from each other by the sense of touch.
Now, a device and method has been invented for implementing a key that enables customization of the keyxe2x80x94and thus the whole user interfacexe2x80x94just as in the case of touch screens, and provides the possibility to operate the key relying on the sense of touch.
According to a first aspect of the invention, there is implemented a key element that characteristically comprises a first layer comprising a material whose volume is responsive to the magnitude of field, said field being one of the following: electric field, magnetic field, both of the above; and means for altering the field in a wanted position in said layer in order to create a key in that position.
According to a second aspect of the invention, there is implemented a key element that characteristically comprises a first layer comprising a material whose volume is responsive to the magnitude of field, said field being one of the following: electric field, magnetic field, both of the above; means for detecting a press and means for altering said field to create a pressing of the key in response to the detected key press.
According to a third aspect of the invention, there is implemented a method for implementing a key that characteristically comprises the alteration of a field applied at a certain position to a first layer comprising a material whose volume is responsive to the magnitude of the field, to create a key in said position; said field being one of the following: electric field, magnetic field, both of the above.
According to a fourth aspect of the invention, there is implemented an electronic device that characteristically comprises a layer comprising a material whose volume is responsive to the magnitude of field, said field being one of the following: electric field, magnetic field, both of the above; and means for altering the field in a wanted position in said layer to create a key in that position.
According to a fifth aspect of the invention, there is implemented a manufacturing method for manufacturing a key element, the method characteristically comprising the joining of a layer of a material whose volume is responsive to the magnitude of field with means for altering said field, the field being one of the following: electric field, magnetic field, both of the above.
A preferred embodiment of the invention utilizes material whose volume is responsive to the magnitude of an electric field, so-called MSM material (Magneto Straining Material). It is also possible to alter the volume of many of these materials by altering the magnitude of a magnetic field applied to the material. A characteristic of MSM materials is the change in volume in connection with the changes to an electric field, magnetic field or both fields applied to the material. An example of such a material whose volume is responsive to the magnitude of field is the material Ni2MnGa, featured in publication WO 99/45631; by redirecting the dual structure of the material using an electric field, a reversible change in the material volume can be obtained. In prior art, it is commonly known that there are materials whose changes in volume are irreversible, i.e., the material will not return to its original size even if the electric and/or magnetic field applied to the material would return to its original magnitude. One of these irreversible materials is Polypyrol.
A preferred embodiment additionally utilizes material whose electrical conductivity is responsive to pressure, so-called ER material (elastoresistive material). A characteristic of these materials is that the electrical conductivity of the material changes in connection with changes to the pressure applied to the material. The position of pressure applied to the material, e.g., a press of a finger, can be determined preferably by means of a conductor matrix connected to the material. Another preferred alternative for the detection of finger presses is, for example, the use of ElectroMechanical Film (EMFi) material, as featured in publication EP 775049. Whereas the electrical conductivity of ER material increases in connection with the increase in pressure applied to the material, EMFI material directly produces electricity from pressure, i.e., EMFI material produces an electrical voltage when compressed or moved. Also the detection of pressure is done in a slightly different way with these materials; whereas EMFI material directly produces electricity when pressed, and this electricity can be detected and its position determined with a conductor matrix, with ER material it is required to feed the conductor matrix with external current that is transmitted from one conductor to another through the ER membrane at a crossing point of the conductors when pressed.
A preferred embodiment of the invention also utilizes a membrane created with so-called electronic ink (E-ink). An image is created on the E-ink membrane by using an electric field to control micro-capsuled color cells in the membrane; one part of the capsules comprises dark-colored cells, and another part comprises light-colored cells. By turning these micro-capsules to different positions, it is possible to create different shades of dark and light areas on the membrane, as in a conventional black-and-white television. Electronic paper has been discussed, for example, in the article xe2x80x9cDigital Ink Grants every Whimxe2x80x9d, published in the Financial Times on Mar. 11, 1996.
In a preferred embodiment, the device and method are used as the user interface of an electronic device. The key that is the object of the invention has the characteristic feature that it can be customized whenever necessary, so a separate user interface is not necessary when the requirements change. In case of a key pad implemented according to this invention, language-specific settings, for example, can be done preferably when the key pad is sold to the customer; this covers, for example, the language that the key pad supports, be it Chinese, Spanish or English. There is no need to stock different key pads for different languages any longer.
The key that is the object of this invention principally works in the same way as current keys in key pads; the selectors are clearly distinguished from the surrounding surface by their height. The differences in the key surfaces create a clear user interface where the boundaries between different selectors are clearly distinguishable and detectable by touch. In addition, when pressing the selector, it will preferably move down, which confirms the user that the pressing operation has been successful.
The key that is the object of the invention can also be employed for the common control of various electronic devices. An user interface comprising keys can at one time be used as the keyboard of a computer, at another time as a game controller with a few selectors, and at a third time as the remote control for a text TV set. With digital convergence, the benefit gained from a user interface adaptable to the situation and environment will increase in the future. Digital convergence means the integration of various different electronic devices into one common device, for example, the integration of a computer, a mobile phone, a PDA and a camera into a single device. Devices created for different purposes require different user interfaces, though, and using prior art solutions, a common integrated user interface would require lots of tradeoffs between the user interfaces of the different devices; this would render the user interface inconvenient and user-unfriendly. However, a user interface implemented using the key according to the invention makes it possible to integrate different electronic devices into one in such a way that all the devices can retain their separate user interfaces. This means that it is not required to attempt to use a camera, for example, by means of a computer keyboard unsuitable for the purpose; when changing over from the computer application to the camera application, the user interface can preferably be changed from a word processor keyboard, for example, into a camera user interface.
The layered key element for the key that is the object of the invention can be created preferably by sandwiching a layer of a material whose volume is responsive to the magnitude of an electric or magnetic field and a layer of a material whose electrical conductivity is responsive to pressure, with electric or magnetic field matrices controlling these layers and constructed from a set of electrodes and/or coils when using a magnetic field; these can preferably be active or passive matrices. In addition to these layers, an E-ink layer can be preferably sandwiched on the key element; this makes it possible to integrate a display with the key element. A layer of material can be preferably placed below the E-ink layer and its control matrix, comprising a material whose volume expands with the added magnitude of an electric or magnetic field, and a matrix controlling this layer of material. An ER layer can be preferably placed under these layers, comprising a material whose electrical conductivity increases with increasing pressure. On both sides of the ER layer, parallel conductor field layers will be placed in a perpendicular orientation with each other. A material layer comprising a material whose volume decreases with the added magnitude of an electric and/or magnetic field, and a matrix controlling this layer, will be preferably placed at the bottom.
Using the method according to the invention, the key can be made to operate by raising the selector from the surrounding surface, using the appropriate control matrix to increase the magnitude of the electric or magnetic field applied to the layer comprising a material whose volume expands with the added magnitude of the electric and/or magnetic field. The press of the selector can be preferably detected and located as a local increase of electrical conductivity in the ER layer, using constant voltage between the perpendicularly oriented conductor layers surrounding the ER layer. The down movement of the key can be achieved by increasing the magnitude of the electric and/or magnetic field applied to the layer of material whose volume decreases with an increase in the magnitude of the electric and/or magnetic field, in the position where the local increase of electrical conductivity was detected in the ER layer. As a consequence of this, said layer of material will be compressed at the position of the key press, which means that the key is able to move down and give the user the feeling that the key press was successful. Correspondingly, as the electrical conductivity of the ER layer returns to normal, the magnitude of the electric or magnetic field applied to the layer of material whose volume decreases with an increase in the magnitude of the electric and/or magnetic field, in the position where the local increase of electrical conductivity was detected in the ER layer, will also be returned to its normal value. As a consequence of this, the thickness of said layer of material will return to its original value, which causes the key to return up to its original position.
One benefit of the key that is the object of the invention is its very wide applicability for installation to various places. Because the key-based user interface has a flat surface when the electric field is switched off, it can be preferably embedded, for example, in a table-top, a wall or a piece of furniture. The material can also be effectively used for coating a monitor surface, a mobile phone or another electronic device. The benefits of this method include the savings in component usage with the integration of various devices, as the same components can be used to implement various software-controlled tasks to a greater extent.
By using the key device that is the object of the invention, an electronic drawing board can be preferably implemented using the configuration described above. In the drawing board application, at least a part of the key element will be left as a flat drawing surface, on which it is possible to draw preferably by pressing the surface with a suitable pen or a finger, for example. The pressure on the surface can be effectively detected in the ER layer, and the surface can be raised up at the position of pressure by increasing the magnitude of the electric and/or magnetic field applied to the layer comprising a material whose volume expands with the added magnitude of the electric and/or magnetic field, thus creating a three-dimensional plot. It is also possible to preferably determine the height of the raised surface based on the magnitude or the duration of the key press, which may be used to improve visualization by varying the output height from the surface. If three-dimensionality is not needed, but a drawing plot is enough, this can be achieved effectively by controlling the imaging in the E-ink layer. This can be preferably implemented in the matrix controlling the E-ink layer, e.g., by darkening the surface at the touched spot and keeping the background light, or vice versa. If desired, the darkness of the touched spot can also be preferably adjusted based on the magnitude or duration of the touch, for example.
By implementing the device that is the object of the invention, it is also possible to preferably implement a user interface for the weak-eyed. This can be preferably achieved by raising areas or letters up from the user interface surfacexe2x80x94the weak-eyed user could interpret these by the sense of touch in fingers. It would be possible to preferably implement this by using an application controlling the magnitude of the electric field applied to a layer of material whose volume increases with the increase of magnitude in the electric field, to represent the desired information in an area of the user interface surface.
It is even possible to generate sound with the device that is the object of the invention.
The sound generating function can be preferably generated by quickly moving the surface of the layered material element that is the object of the invention, like a loudspeaker cone, by quickly varying the magnitude of an electric and/or magnetic field applied to the layer or layers of material whose volume is responsive to the magnitude of an electric and/or magnetic field. The device that is the object of the invention can also be used for implementing noise-cancelling generators.